Chapter 40

1. Chapter 40 Basic Principles of Animal Form and Function

2. Animals inhabit almost every part of the biosphere • Animals must obtain oxygen, nourish themselves, excavate waste and move • Anatomy- the structure of an organism • Physiology- study of the functions an organism performs

3. -Example of evolutionary convergence: due to the similar environment organisms adapt to have the same attributes to survive

4. The body plan of animals resulted from a patter of development programmed by their changing genomes • Animal size and shape directly affect the exchange of energy and materials

5. Exchange with the Environment • When substances dissolve into an aqueous medium and diffuse to transport across the plasma membrane • Single celled organisms have enough surface area of plasma membrane to service it’s cytoplasm • Organisms with a sac body have a body structure that facilitates the diffusion of materials • More complex organisms have internal surfaces to exchange materials.

6. Animal form and function: Level of orgainization • Composed of cells • Tissues: Cells with a common function or structure • Tissues make up organs • Multiple organs make up organ systems

7. Mucosa. The mucosa is an epithelial layer that lines the lumen. Submucosa. The submucosa is a matrix of connective tissue that contains blood vessels and nerves. Muscularis. The muscularis consistsmainly of smooth muscle tissue. Serosa. External to the muscularis is the serosa,a thin layer of connective and epithelial tissue.

8. Tissues are all structured in order to perform specific functions • There are four diff. types of tissues -Epithelial - Connective - Muscle - Nervous

9. Epithelial tissues • Lines the organs and cavities, and covers the outside of the body • Cells are closely joined • Connective tissue • Binds and supports other tissues • The cells are sparsely packed throughout the extracellular matrix

10. Muscle tissue • Composed of muscle fibers, which contract to nerve signals • Divided into three types: skeletal, cardiac, and smooth • Nervous tissues • Senses stimuli and sends signals throughout the organism

11. Organs and organ systems • Most complex animals have organs • Different tissues are organized as organs • Some organs are composed of tissues arranged in layers • Organ systems carry out major body functions

12. Organ systems

13. Animals need chemical energy for -growth -repairs -physiological processes -regulation -reproduction • Bioenergetics: flow of energy through an animal -limits behavior, growth, and reproduction, and amnt of food

14. Studying bioenergetics can determine the animals adaptations • Animals harvest chemical energy from the food they eat • They use the energy to make ATP • Once the energetic needs are met, the rest of the energy goes to biosynthesis • Metabolic rate: the amount of energy and organism uses in a specific time -measured in different way

15. Measure the intake of oxygen consumed, or the carbon dioxide produced • Metabolic rate is correlated to bioenergetic strategy • Mammals and birds are endothermic • Their bodies are warmed by the heat generated by their metabolism • Have higher metabolic rates

16. Reptiles and amphibians are ectothermic • Gain their heat from outside sources, lowering their metabolic rate • Many factors affect metabolic rate • Rate per gram - inversely related to the size of the animal • Basal metabolic rate(BMR)- endotherm at rest • Standard metabolic rate(SMR)- ectotherm at rest

17. Activity affects metabolic rate • Maximum metabolic rate is related to the duration of it’s activity • Depending on the environment, the energy and materials are used differently • The use of energy is divided into BMR (SMR), activity, homeostasis, growth and reproduction

18. interstitial fluid: The internal environment of vertebrates • Homeostasis is the balance between the environmental changes and the internal control mechanisms • Animals cope with environmental fluctuations through regulation and conforming • A regulator changes internally to moderate the changes externally • A conformer allows the internal environment to vary with the environment around it.

19. Response No heat produced Heater turned off Room temperature decreases Set point Too hot Set point Too cold Set point Control center: thermostat Room temperature increases Heater turned on Response Heat produced • Mechanisms of homeostasis • A homeostatic control system has a receptor, a control center, and an effector.

20. Either controlled by negative or positive feedback • negative feedback: when a build up of the end product signals a stop. • Positive feedback: when a change in a variable causes an increases the change • Thermoregulation: process that helps animals maintain their internal temperature

21. Ectotherms: most invertebrates, fishes, amphibians, and non aviary reptiles • Endotherms: birds and mammals • Ectotherms have a greater range of internal temperature • Endothermic animals use more energy, but helps the animal avoid external fluctuations, and gives them a high level of aerobic metabolism

22. Organisms exchange heat by radiation, evaporation, convection, and conduction. Radiation is the emission of electromagnetic waves by all objects warmer than absolute zero. Radiation can transfer heat between objects that are not in direct contact, as when a lizard absorbs heat radiating from the sun. Evaporation is the removal of heat from the surface of a liquid that is losing some of its molecules as gas. Evaporation of water from a lizard’s moist surfaces that are exposed to the environment has a strong cooling effect. Conduction is the direct transfer of thermal motion (heat) between molecules of objects in direct contact with each other, as when a lizard sits on a hot rock. Convection is the transfer of heat by the movement of air or liquid past a surface, as when a breeze contributes to heat loss from a lizard’s dry skin, or blood moves heat from the body core to the extremities.

23. Thermoregulation uses psychological and behavioral changes to balance heat gain and loss • Insulation (blubber, feathers, fur) reduces the exchange of heat between the animal and it’s environment • Integumentary system is an insulating system in humans • Many endotherms and some ectotherms can regulate the blood flow between the body core and skin

24. Vasodilatation: blood flow in the skin increases • Vasoconstriction: blood flow in the skin decreases • Marine mammals and birds(as well as some bony fishes and sharks) have blood vessels arranged to prevent heat loss (concurrent heat exchangers) • Endothermic insects have concurrent heat exchangers that help keep a high tmp in their thorax

25. Many animals maintain their tmp by sweating, panting, or bathing • Endotherms and ectotherms use behavioral responses to control body temp • Some terrestrial invertebrates have positions that help them maximize, or minimize the absorption of heat • Some animals can adjust their metabolic heat production • Flying insects shiver before taking flight to warm up

26. Mammals use negative feedback to regulate their body temp • The hypothalamus contains cells that function as a thermostat (in the human brain) • Acclimatization is when an animal adjusts to a temperature over a couple days or weeks • May involve adjustments of the insulation and metabloic heat regulation (in birds and mammals

27. Torpor: method that helps animals save heat without dangerous conditions, it is a psychological condition that makes activity low. • Hibernation is an extended torpor which occurs when the temperature drops • Estivation (summer hibernation): allows the animal to survive high temperatures and scarce water • Daily torpor: adapted from the feeding patterns of birds and small mammal